Camera Memory Card Types

Camera Memory Card Types: which one to buy

Why get a memory card?

The purpose of memory cards is to easily store and transfer data from one device to another.

You can store all sorts of media on them, including MP3 and MP4 files, as well as Microsoft Word documents.

There are so many different types of memory cards out there, available in all sorts of shapes, sizes and speeds, but not all of them are made for photography.

In addition, there are several factors to consider before purchasing a memory card that will not only be compatible with your camera, but also with your shooting style.

Types of memory cards

Cameras have a slot that has been specifically designed to house a memory card.

The slot in your camera is most likely built for a Secure Digital derivative type card. However, CompactFlash cards are also common.

SD - Secure Digital

Secure Digital (SD) cards were introduced by SanDisk in 1999.

Since then, many improvements have been made and the SD card has branched out into two different subtypes, the SDHC and SDXC.

The original SD card is still widely used, but due to its age this card is relatively slow compared to its descendants.

For this reason, the plane and simple SD card isn’t ideal for shooting high resolution or RAW photos.

However, the original SD card is a practical choice if you’re an amateur photographer, or use cheaper digital cameras that don’t require a lot of speed.

All SD derivatives are rectangular but have a really small fifth side on the top right hand corner.

SDHC - Secure Digital High Capacity

Secure Digital High Capacity (SDHC) cards were introduced in 2006. Over a decade later, they are still one of the most reliable and widely used types of cards out there.

In the past, these cards generally offered a capacity of between 4GB and 32GB, but it’s now possible to buy an SDHC card with up to 512GB.

These cards are a great option for photographers who need speed but don’t hold it as their highest priority. They work with any SD-compatible camera, as long as the camera was built after the SDHC was introduced in 2006.

SDXC - Secure Digital ‘Xtra Capacity

Secure Digital ‘Xtra Capacity (SDXC) cards are the newest and fastest type of SD derivative on the market. These cards were introduced by SanDisk in 2011, and have the highest memory capacity (up to 1TB).

Like the SDHC, this card also fits SD slots, but again, you may not be able to use this card if your camera (or computer) was built before the SDXC’s creation.

CF - Compact Flash

CompactFlash (CF) cards, one of the oldest types of memory cards, were introduced by SanDisk in 1994.

These cards are square in shape, and come in two different subtypes: CFI, which is 3.3mm thick, and CFII, which are 5mm thick.

CF cards are not as common as they used to be, but due to their high speed and physical durability, many advanced DSLR cameras are still built to accommodate them.

Their Ultra Direct Memory Access (UDMA) mode systems are a way for the user to determine the speed of the chip. A number between zero and seven is written on each card; zero is the slowest speed, allowing up to 16.7MB/s, while mode 7 allows up to 167MB/s.


The speed of a memory card determines how quickly data can be transferred to and from the card.

This may not be a vital aspect to consider if you take JPEG images at a slow pace, but if you shoot in RAW and/or shoot in bursts, you’ll definitely be let down if you don’t get a card with a fast enough speed.

Also, understanding how card speed works is really important if you want to avoid getting confused during your search for the right memory card.

Reading and Writing Speeds

Each card has a reading speed and a writing speed.

The reading speed refers to the maximum speed that data is transferred to the memory card after you take a photo. If you use a card with a slow reading speed of 4MB/s, you will find it difficult to take photos at a fast pace, regardless of the file sizes.

If you’re a photographer who needs to shoot in quick bursts or RAW files then you’ll need a card that can quickly read the high volume of data that these files produce at high rates.

The writing speed refers to the maximum speed that data is transferred from the memory card to a device, such as a computer or printer.

Keep in mind that the card manufacturer will likely list a memory card’s maximum speed rather than its average speed.

Speed Ratings

For this reason, it’s a good idea to be familiar with speed classes and ratings so you can make a generalization about which speed class you want your card to belong to.

Cards are also given a speed rating, such as 400x or 1000x; the bigger the number before the ‘x,’ the faster the speed.

If you look at the face of a memory card, it probably has a number with a circle around it. This number represents the card’s speed class; Class 10 is the highest, and guarantees a transfer speed of 10MB/s, while Class 2 is the slowest and works at a speed of 2MB/s.

If you look at a memory card and see a U shape with a number between one and three, that means the card has an Ultra High Speed (UHS) rating.

The number within the U shape represents the UHS tier the card belongs to; UHS-1 is the slowest tier (10MB/s minimum), and UHS-3 is the fastest (30MB/s minimum).

Also, keep in mind that some of the faster types of memory cards might make your camera’s battery drain faster.


The amount of capacity your card should have depends on the quality and quantity of the images you intend to keep on your memory card at a time.

Image sizes are determined by their resolution and compression level. A camera with a high resolution sensor will produce large file sizes unless you tweak your settings to make the images smaller.

Many people save their images as JPEGs in order to save space on their memory card. I prefer to shoot in RAW so that I can have more control over the editing process, so my memory cards are all 32GB or larger.

If you save your files as JPEGs, you should be able to get away with using a 16GB memory card.

You can use a calculator like this one to determine your ideal card’s capacity. Of course, you can always buy more than one memory card as long as you have a safe place to store them

A few more things to be aware of

Before purchasing a memory card, remember that you need to ensure your devices are compatible with it.

Most computers do have a little slot where you can insert a memory card (usually an SD derivative), but some don’t, so you may need to purchase a card reader in order to transfer your photos to your computer.

Also, make sure you are buying a reliable memory card. Sticking with a well-known brand (such as SanDisk and Lexar) is always a better option than going for a brand you haven’t heard of.

According to SanDisk, their memory cards have 1,000,000 hours of life in them.

Always treat your memory cards with care, and always eject them from your computer before removing them.

Memory Cards Reviewed

SanDisk Ultra SDXC Memory Card


  • Affordable
  • Relatively fast
  • Highly durable


  • Not for speed demons
  • Not ideal for use with advanced DSLRs

The SanDisk Ultra SDXC card is a good choice photographers who are looking for something durable and relatively fast, but hold speed as their greatest priority.

This SanDisk Ultra SDXC card is a Class 10, and transfers data at rates up to 80MB/s.

I have been using this card as a spare for years, and it’s just as reliable now as it was the day I bought it. However, it definitely works better with my Samsung NX1000 than it does with my Nikon D600.

Using this card, I can shoot bursts of just about 10 RAW photos, but it takes about 30 seconds for my card to read them.

This card seems to have a low buffer threshold, so after your initial burst of photos you may notice that the card’s reading speed slows down significantly.

There are definitely faster cards out there, so if you're hoping to be shooting action or bursts of RAW photos I would recommend skipping this option and going for a faster one.

This card works best if you frequently transfer your photos from your card to your computer.

This card has 64GB or RAM and should be compatible with any camera with an SD slot made after 2011.

It may not be the fastest card, but it’s incredibly durable.

It can survive extreme temperatures on either side of the spectrum, so if you’re planning a winter trip to the tundra or a summer holiday on the equator, this card will be a nice companion.

SanDisk Extreme Pro SDHC UHS-3 Card


  • Affordable
  • Fast
  • Highly durable


  • May perform slower with certain devices 

This is my go-to SDHC card, and it has yet to fail me. The smallest card you can get is 16GB, and, if you’re willing to throw down a couple hundred dollars, the largest is 512GB.

Personally, I settled for 32GB and I’ve had no problems. Then again, my camera (Nikon D600) does have two memory card slots, so I don’t depend on one chip at a time.

This card records data at a maximum of 90MB/s, and transfers it at 95MB/s; I can shoot quick bursts of 12 RAW photos, and it takes less than 10 seconds for all of them to load to the card. If you shoot a lot of action, then I highly recommend this card.

I’ve had mine for about five years; it’s survived several falls and has been rained on and it’s still working perfectly. I’m able to shoot RAW files in bursts with this card.

AND its buffer threshold is quite high, so I can continue taking photos at a slower rate after the initial burst is over. I can also shoot great videos using this card with hardly any delay.

This card also comes with RescuePRO Delux data recovery software; if you accidentally delete files, have no fear! You can recover them with a single free download.

This chip is also available as a CompactFlash card.

Lexar Professional 633x SDXC


  • Two-in-one
  • Class 10
  • Image rescue software


  • 20MB/s writing speed

It’s hard to say no to a good two-in-one deal! This is a two-pack of 64GB cards, but you also have the option of buying a single pack, and the capacity goes up to 512GB if you’re willing to pay the extra price.

This is a class 10 card with a reading speed of up to 95MB/s, and a 20MB/s writing speed, so it’s definitely best for photographers with a bit of patience.

This option includes downloadable Image Rescue software, so you don’t need to stress out if you accidentally delete some files.

A few of my photography club peers use this card. The street photographers love it, but the action photographers wish it was faster. If you’re into sports photography, videos or shooting RAW files in bursts then this card probably isn’t the best option for you.

But if you’re on a budget, then this is a really good deal.

Lexar Professional 1000x 64GB SDXC


  • 150 MB/s reading speed
  • Image recovery software


  • Faster with some cameras than it is with others

This card is available with several different capacity options — all for a reasonable price. It has a maximum reading speed of 150MB/s and a writing speed of 80MB/s.

You can buy this card with a capacity as low as 16GB, and as high as 256GB.

This card is UHS-2, so, yes, it’s quite fast, but Lexar warns that you won’t get the most out of its writing speed unless you use it with an SD UHS-2 card reader.

You should also check your camera before buying this if you want to get the most out of its speed. You should be able to shoot at least 25 high resolution images in one burst with this card, but you may not have such luck if you use it with a Nikon — that’s why I don’t use it.

This card works really well with Sony, Olympus and Canon cameras.

This memory card also offers image recovery software, just in case you accidentally delete your files. Whew!

Eyefi Mobi 8GB WiFi SDHC 


  • Wireless image transfers
  • Unlimited cloud storage


  • Not compatible with RAW files
  • Pricey

If you’re one to roll with the times, perhaps you should try out this relatively unconventional option. It uses wifi to transfer your photos from your camera to any of your devices as you take them, so the fact that this card’s capacity is 8GB shouldn’t be a problem.

If you buy this card, you also get a 90 day Eyefi Cloud membership, which provides unlimited storage. If you like the card, who knows, it may be worth spending the extra bucks on a full membership.

Somebody gave this to me as a gift, and I think it’s a great novelty that has a solid future but it’s obviously not great for shooting in bursts and, unfortunately for me, the wifi function is not compatible with RAW files.

To get the most out of this card, you need to have access to wifi, which obviously works faster with smaller images.

If you want to share JPEG images on your social media accounts as soon as you take them, this is a great option.

It may not be my ideal card, but I am really happy that I am in possession of one because it’s really cool and can definitely be super convenient.


Photographers have so many options when it comes to choosing a memory card. In order to prevent disappointment, it’s really important to find a card of the right type, speed and capacity to suit your needs.

There is no one-size-fits-all memory card; but if there was, it would be the SanDisk Extreme PRO SDHC card because its value for money is the least likely to let you down.

It’s super fast and reliable, and available with a wide range of capacities. It is an SD derivative, so it will most likely fit in your camera and your computer.

If you’re not in need of this card’s great speed, I still recommend it because you never know when its functions will come in handy in the future.

Camera Memory Card Types

Check out more Accessories Reviews here 

About the Author Luca

Hi, I am Luca, founder and editor in chief at I am crazy about photography and I always have a camera with me. When I am not busy with my day job, enjoying my family or taking photos, I am on Photography Ambition to share what I have learnt so far.

Leave a Comment: